Reciprocating pumps are commonly used to pump mixtures of liquids and solids for process and transportation purposes. Reciprocating pumps are particularly suited to these applications because of their relatively low velocities compared to centrifugal pumps. Lower velocity pumps are preferable for use in pumping mixtures of liquids and solids because erosive wear rates have been discovered to be proportional to a fairly high exponent (3 to 4) of the relative velocity of the pump. However, the close operating clearances required in reciprocating pumps, such as at the plunger or piston rod packing, are particularly subject to abrasive wear. For this reason, it has proven desirable to provide a flushing mechanism to reciprocating pumps in order to minimize the presence of abrasive particles in these close clearance areas.